Method of extracting virus genes and extraction apparatus

ABSTRACT

The present invention provides a method of extracting virus genes, which is excellent in quickness and convenience and can be automated, and this invention also provides an apparatus for such extraction of virus genes. A conductive hollow fiber membrane (module)  12  is immersed in a virus suspension  20  and thus viral particles suspended in the virus suspension  20  are captured in the conductive hollow fiber membrane (module)  12 . The coating of the thus captured virus is lysed and the virus genes are released. Next, the virus genes are collected by subjecting the conductive hollow fiber membrane (module)  12  to at least one of an electrical treatment and a physical treatment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is filed under the provisions of 35 U.S.C. §371 andclaims the priority of International Patent Application No.PCT/JP01/02118 filed 16 Mar. 2001, which in turn claims priority ofJapanese Patent Application No. 2001-63834 filed 7 Mar. 2001.

BACKGROUND

The present invention relates to a method of extracting virus genes aswell as an apparatus for such extraction. Particularly, this inventionrelates to a method and an apparatus for extracting virus genes by meansof electrophoresis, using a conductive hollow fiber membrane.

Among virus infectious diseases, those caused by hepatitis viruses orhuman immuno-deficiency viruses (HIV) may lead to fatal diseases such asliver cirrhosis, liver cancer, or acquired immune deficiency syndrome(AIDS). Present diagnoses for these infectious diseases include anantibody assay, virus culture, and gene diagnosis. However, the antibodyassay has problems in that it takes a very long period of time toconfirm an antibody, and that before the antibody is confirmed, thepatient may be given a false negative diagnosis.

The virus culture has some drawbacks, including: culturing methods arenot established regarding some types of viruses; but even the viruseswhich can be cultured, have cultured cells which are different from eachother; and it requires a considerable amount of time to culture thesecells. On the other hand, the gene diagnosis requires many manualoperations which are complicated. However, since the diagnosis can beconducted quickly, the gene diagnosis has been employed in many cases.

In the gene diagnosis, it is necessary to extract virus genes from aspecimen, for which a chemical treatment is employed. However, theextraction procedures are complicated and require many manual oprations, which in fact have not been automated. When the number ofviruses in a specimen is small, it is necessary to apply a pretreatmentof virus enrichment by means of an ultracentrifuge for a long period oftime, which is burdensome.

SUMMARY

The present invention aims to solve the above-described conventionalproblems. It is an object of this invention to provide a method ofextracting virus genes, which is excellent in quickness and convenienceand can be automated, and to also provide an apparatus for such virusgene extraction.

In order to achieve this object, this invention provides a method ofextracting virus genes from a virus suspension, comprising the steps of:immersing a conductive hollow fiber membrane in the virus suspension andthereby capturing, in the conductive hollow fiber membrane, virusessuspended in the virus suspension; lysing the coating of the capturedviruses and releasing the virus genes; and collecting the virus genes bysubjecting, after the lysing step, the conductive hollow fiber membraneto at least one of an electrical treatment and a physical treatment.

The capturing step can include a step of aspirating the virus suspensionvia the conductive hollow fiber membrane.

The electrical treatment can include a step of conducting lectrophoresisby energizing the conductive hollow fiber membrane so that theconductive hollow fiber membrane becomes a cathode.

The physical treatment can include a step of forcing back, via theconductive hollow fiber membrane, the virus suspension that has beenaspirated in the aspirating step.

Moreover, in the gene-collecting step, the electrical treatment and thephysical treatment can be conducted at the same time.

Also, the coating of the viruses can be lysed chemically in the lysingstep.

Furthermore, the electrophoresis step can be conducted by placing asemipermeable membrane between the cathode area and an anode area.

This invention also provides a virus gene extracting apparatus forextracting virus genes from a virus suspension, comprising: a conductivehollow fiber membrane immersed in the virus suspension in order tocapture viruses in the virus suspension; a lysing liquid for lysing thecoating of the viruses captured in the conductive hollow fiber membraneand releasing the virus genes; and a gene-collecting device which iscapable of receiving the conductive hollow fiber membrane with thereleased virus genes captured therein, and which applies at least one ofan electrical treatment and a physical treatment to the virus genescaptured in the conductive hollow fiber membrane, thereby collecting thevirus genes.

The virus gene extracting apparatus can further comprise a pump that isconnected to the conductive hollow fiber membrane and is capable ofaspirating the virus suspension via the conductive hollow fibermembrane.

The gene-collecting device can include an energizing device forenergizing the conductive hollow fiber membrane so that the conductinghollow fiber membrane becomes a cathode.

Moreover, the gene-collecting device can include a mechanism for forcingback, via the conductive hollow fiber membrane, the virus suspensionthat has been aspirated by the pump.

Furthermore, a semipermeable membrane can be placed between the cathodearea and an anode area.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a capturing device for capturingviruses in a conductive hollow fiber membrane according to an embodimentof this invention.

FIG. 2 is a fragmentary sectional view of the device of FIG. 1.

FIG. 3 is a schematic diagram of a gene-collecting device for collectingvirus genes captured in the conductive hollow fiber membrane accordingto the embodiment of this invention.

FIG. 4 is a diagrammatic illustration of the structure of a virus.

FIG. 5 shows the results of electrical and physical gene extractionaccording to the embodiment of this invention.

FIG. 6 shows the gene extraction results with regard to electric fieldapplication time and electric field strength according to the embodimentof this invention.

FIG. 7 shows the gene extraction results by utilizing the enrichmenteffect according to the embodiment of this invention.

FIG. 8 shows the gene extraction results by using the conductive hollowfiber membrane and by limiting a virus concentration range according tothe embodiment of this invention.

DETAILED DESCRIPTION

A preferred embodiment of the method and apparatus for extracting virusgenes according to this invention is described below with reference tothe attached drawings.

FIG. 1 is a schematic diagram of a capturing device for capturingviruses in a conductive hollow fiber membrane. FIG. 2 is a fragmentarysectional view of the device of FIG. 1. FIG. 3 is a schematic diagram ofa gene-collecting device for collecting virus genes captured in theconductive hollow fiber membrane. FIG. 4 is a diagrammatic illustrationof the structure of a virus.

The virus gene extracting apparatus of this invention comprises acapturing device 10 for capturing viruses in the conductive hollow fibermembrane, and a gene-collecting device for collecting the virus genescaptured in the conductive hollow fiber membrane.

The capturing device 10 shown in FIGS. 1 and 2 comprises: a container 11which contains a virus suspension 20; a conductive hollow fiber membranemodule 12 for capturing viruses suspended in the virus suspension 20; asilicon tube 13 connected to the conductive hollow fiber membrane module12; a pump 14 that is connected via the silicon tube 13 to theconductive hollow fiber membrane module 12 and is capable of aspiratingthe virus suspension 20 via the conductive hollow fiber membrane module12; and a collecting container 15 for collecting the aspirated solution.

Concerning a virus used for this embodiment, herpes simplex virus type 1(HSV) which has a relatively low risk and can be easily cultured isemployed as a DNA virus similar to the hepatitis B virus (HBV).

As shown in FIG. 4, this virus 21 has a regular icosahedron nucleocapsidstructure, which means that the arrangement of a capsid (protein coat)forms a regular icosahedron, which contains nucleic acids 22 (DNA) atits center. The outside of the structure is covered with an envelope 23that is composed of lipid and glycoprotein. The size of this virus isapproximately 150 nm to 200 nm in outside diameter.

In this embodiment, the liquid in which the viruses are suspended isdiluted with a buffer solution for electrophoresis, and the obtainedvirus suspension 20 at a concentration of approximately 5×10³ to 5×10⁶TCID₁₀₀/ml is used.

There is no particular limitation on the type of the container 11 aslong as it is capable of containing the conductive hollow fiber membranemodule 12 and the virus suspension 20. The details of the container 11,such as its shape or size, can be decided as appropriate according to,for example, the scale of the virus gene extraction.

The conductive hollow fiber membrane module 12 is structured in such amanner that a lead wire for energization is fixed with low meltingsolder at one end of a conductive hollow fiber membrane that has beencut to the length of approximately 2 cm, and the obtained conductivehollow fiber membrane is then connected to a solution aspirating nozzle,and the connection is fixed with epoxy resin. The other end of thisconductive hollow fiber membrane module 12 is sealed with epoxy resin sothat the solution can be aspirated via the conductive hollow fibermembrane. Because of this treatment, the effective length of theconductive hollow fiber membrane is approximately 1 cm.

In this embodiment, as the conductive hollow fiber membrane, apolypropylene hollow fiber membrane, which, for example, is used forsimplified water purifiers in common use, and whose surface is coatedwith metal (such as gold [Au]) by electroless plating, is employed.

The shape of the conductive hollow fiber membrane is, for example, acylinder (for example, approximately 1.8 mm in outside diameter andapproximately 1.2 mm in inside diameter). Regarding the conductivehollow fibers, polypropylene fibers are coated with metal to the depthof several tens of μm from the outside surface of th membrane, so thatthe inner part of the polypropylen fibers which are not coated withmetal is formed as a polypropylene layer, which is what the hollow fibermembrane originally is. The polypropylene layer and the metal layer havesponge-like pores (the pore sizes, for example, are approximately 0.1μm). The value of resistance of this conductive hollow fiber membrane isapproximately 0.2 Ω/cm to 1.0 Ω/cm.

The gene-collecting device as schematically shown in FIG. 3 comprises:an electrophoresis tank 41; a semipermeable membrane 42 to divide theInside of the electrophoresis tank 41 into two areas; an anode 43located in one of the areas of the electrophoresis tank 41 as divided bythe semipermeable membrane 42; a cathode 44 located n the other area ofthe electrophoresis tan 41 as divided by the semipermeable membrane 42;an energizing device 45 connected to the anode 43 and the cathode 44;and a mechanism 46 for forcing back, via the conductive hollow fibermembrane module 12, the solution aspirated by the pump 14 in thecapturing device 10.

As the anode 43, for example, a platinum wire can be used. On the otherhand, the cathode 44 is composed of the conductive hollow fiber membranemodule 12 in which the virus genes released by the above-describedcapturing device 10 are captured.

The mechanism for forcing back, via the conductive hollow fiber membranemodule 12, the solution aspirated by the pump 14 in the capturing device10 is made by connecting the silicon tube 13, the pump 14, and thecollecting container 15 to the conductive hollow fiber membrane module12. The mechanism is structured so as to force back the solution byoperating the pump in reverse.

The virus gene extraction was conducted by the following method, usingthe above-described apparatus for extracting virus genes.

First, the conductive hollow fiber membrane module 12 which wasconnected via the silicon tube 13 to the pump (Perista pump) 14 wasimmersed in approximately 4 ml of the virus suspension 20 contained inthe container 1. The virus suspension 20 was then aspirated at anaverage speed of approximately 0.6 ml/min. This operation caused theviruses suspended in the virus suspension 20 to be captured in theconductive hollow fiber membrane. The solution aspirated via theconductive hollow fiber membrane module 12 was collected in thecollecting container in order to examine the enrichment effect on thevirus in the conductive hollow fiber membrane. The aspiration wasstopped when the volume of the remaining virus suspension 20 became 1ml, that is, when 3 ml of the virus suspension 20 was aspirated, and thevirus concentration was thereby terminated.

Subsequently, the conductive hollow fiber membrane module 12 in whichthe virus was captured was immersed in a virus lysing liquid for about10 seconds, thereby chemically lysing the virus coating (i.e., theenvelope 23 and the capsid). In this embodiment, a liquid mixture of 1%SDS and 10 mM NaOH was used as the virus lysing liquid. Accordingly, thevirus genes (nucleic acids 22) captured in the conductive bollow fibermembrane module 12 were released.

The conductive hollow fiber membrane module 12, in which the thusreleased virus genes (nucleic acids 22) were captured, and a platinumwire were set in the electrophoresis tank 41 so that the conductivehollow fiber membrane module 12 would become the cathode 44 and theplatinum wire would become the anode 43. The solution aspirated via theconductive hollow fiber membrane module 12 at the time of virusconcentration was then forced back and, at the same time, an electricfield was applied to the anode 43 and the cathode 44, thereby conductingelectrophoresis. The electric field strength was either 2 V/cm or 4V/cm, and the application time was selected from among 5 minutes, 10minutes, and 15 minutes,

As described above, in the electrophoresis tank 41, the semipermeablemembrane 42 existed between the cathode area, in which the conductivehollow fiber membrane module 12 was located, and the anode area, inwhich the platinum wire was located. Therefore, the extracted virusgenes (nucleic acids 22) existed only in the cathode area. After theelectrophoresis, 5 μl out of approximately 1.5 ml of the solution in thecathode area was used, and 525 base pair (bp) regions of the genescontained in the 5-μl solution were amplified by the polymerase chainreaction (PCR) method. Subsequently, the amplified genes were fractionedby gel electrophoresis, thereby visually confirming whether the geneshad been extracted or not.

Next, after the virus was concentrated and the virus coating was lysedin the same manner as described above, a basic examination was conductedto see whether it was possible to capture the virus genes from theconductive hollow fiber module 12 by conducting electrophoresis, usingthe conductive hollow fiber module 12 as the cathode 44.

FIG. 5 (Lanes 2 and 3) indicates the results of conductingelectrophoresis for 5 minutes with the electric field strength of 2 V/cmafter th virus suspension 20 was aspirated in the amount of 5×10⁴ virusgenes and 5×10⁵ virus genes. As shown in FIG. 5, when the virussuspension 20 with the virus concentration of 5×10⁵ TCID₁₀₀/ml wasaspirated, a gene band was recognized in a range from 492 bp and 615 bp.Since the 525 bp region of the virus genes was amplified by th PCRmethod, it was apparent that the recognized gene band was a virus genefragment, Accordingly, it was shown that the virus genes concentrated inthe conductive hollow fiber membrane could be extracted electrically byconducting electrophoresis, using the conductive hollow fiber membraneas the cathode electrode.

Subsequently, the virus genes were extracted physically and electricallyby forcing back the solution, which had been aspirated via theconductive hollow fiber membrane module 12 at the time of virusconcentration, from the inside of the conductive hollow fiber membranemodule 12 toward the outside thereof and, at the same time, by applyingan electric field to the anode 43 and the cathode 44.

Firstly, by forcing the solution from the inside of the conductivehollow fiber membrane module 12 toward the outside thereof, anexamination was conducted to see whether the virus genes could beextracted physically from the conductive hollow fiber membrane module12.

After the virus concentration and the lysing of the virus coating wereconducted in the same manner as described above, the solution which hadbeen aspirated via the conductive hollow fiber membrane module 12 at thetime of virus concentration was forced out only in the amount (forexample, approximately 1.5 ml) sufficient to be received in the cathodearea of the electrophoresis tank 41 by using the pump 14, but withoutapplying an electric field to the anode 43 or the cathode 44.

Only 5 μl of this forced-out solution was used for the PCR method in thesame manner as described above, and an examination was conducted to seewhether any virus genes were contained in the solution. FIG. 5 (Lanes 4and 5) indicates this result. Referring to FIG. 5, just like in the caseof the electrical extraction of the virus genes, the gene band wasrecognized only in the case where the virus concentration was 5×10⁵TCID₁₀₀/ml. Based on this result, it was confirmed that the virus genesconcentrated in the conductive hollow fiber membrane could be extractedphysically by forcing the solution out, using the pump 14.

Then, after the virus concentration and the lysing of the virus coatingwere conducted in the same manner as described above, the virus geneswere extracted physically and electrically by using the pump 14 to forceout the solution, which had been aspirated via the conductive hollowfiber membrane module 12 at the time of virus concentration, only in theamount (for example, approximately 1.5 ml) sufficient to be received inthe cathode area of the electrophoresis tank 41 and, at the same time,by applying an electric field with the strength of 2 V/cm to the anode43 and the cathode 44 for 5 minutes.

Subsequently, only 5 μl of this forced-out solution was used for the PCRmethod in the same manner as described above, and an examination wasconducted to see whether any virus genes were contained in the solution.FIG. 5 (Lanes 6 and 7) indicates this result. Referring to FIG. 5, justlike in the above-described case, the gene band was recognized only inthe case where the virus concentration was 5×10⁵ TCID₁₀₀/ml.

Accordingly, when either the electrical treatment or the physicaltreatment was applied to extract the virus genes, the virus genes in theamount of up to 5×10⁵ TCID₁₀₀/ml could be xtracted in both cases. Thismeans that both these treatments are effective extraction methods.Therefore, it is conceivable that a combination of these treatments maybe more effective than only one of the treatments to extract the virusgenes.

Next, the electric field application time and strength were examined atthe time of gene virus extraction by means of electrophoresis. In thisexamination, the method of applying an electric field and, at the sametime, forcing out the solution was employed.

As described above, it is apparent that the virus genes can be extractedwith certainty from the conductive hollow fiber membrane, which hasaspirated the virus suspension with the virus concentration of 5×10⁵TCID₁₀₀/ml, by applying the electric field with the strength of 2 V/cmfor 5 minutes. Accordingly, the following examination was conducted withthe electric field strength of 2 V/cm and the 5-minute application timeas the reference.

Firstly, the electric field strength was made constant (2 V/cm) and theapplication time was set to 5 minutes, 10 minutes, and 15 minutes,thereby conducting the virus gene extraction. FIG. 6 (Lanes 2 to 7)indicates the results. FIG. 6 (Lanes 2 to 7) indicates that even if theapplication time was changed from 5 minutes, to 10 minutes, and then to15 minutes, the genes were only extracted up to 5×10⁵ TCID₁₀₀/ml

Subsequently, the application time was made constant (5 minutes) and theelectric field strength of 2 V/cm and 4 V/cm was employed to extract thevirus genes. FIG. 6 (Lanes 8 to 11) indicates the results. It is evidentfrom FIG. 6 (Lanes 8 to 11) that even if the electric fi Id strength waschanged from 2 V/cm to 4 V/cm, the genes were only extracted up to 5×10⁵TCID₁₀₀/ml.

The above-described examinations indicate that the conditions ofelectrophoresis in which the genes can be extracted most efficiently bythe virus gene extracting method of this invention are to set theelectric field strength to 2 V/cm and the application time to 5 minutes.

Next, in order to examine the concentration effect on the viruses in theconductive hollow fiber membrane, the virus concentrations were measuredin the virus suspension and in the solution aspirated via the conductivehollow fiber membrane module. The concentration effect on the viruses inthe conductive hollow fiber membrane was evaluated by comparing theamount of the virus contained in the solutions before and after theaspiration. The virus content is expressed by employing, as an index,tissue culture infectious dose 100% (TCID₁₀₀) which is commonly used forquantitative analysis of viruses. When the amount of active virus islarge, the value of TCID₁₀₀ becomes large. On the other hand, when theamount of active virus is small, the value of TCID₁₀₀ becomes small.Table 1 indicates the results.

TABLE 1 Virus Concentration (TCID₁₀₀) Virus Suspension before Aspiration5 × 10⁶ Virus Suspension after Aspiration <1

Table 1 indicates that the virus concentration of the virus suspensionbefore the aspiration was 5×10⁶ TCID₁₀₀/ml, while the virusconcentration of the solution aspirated via the conductive hollow fibermembrane module was less than 1 virus gene/ml, Accordingly, it has beenconfirmed that all of the virus suspended in the virus suspension can becaptured (or concentrated) in the conductive hollow fiber membrane bycausing the virus suspension to pass through the conductive hollow fibermembrane.

Then, the virus suspension at the concentration of 5×10⁴ TCID₁₀₀/ml,from which genes had not been extracted, was aspirated ten times morethan the aspirated amount in the aforementioned examinations so that theamount of virus in the conductive hollow fiber membrane would become tentimes more than that in the aforementioned examinations, therebyconducting an examination to see whether the virus genes could beextracted in the same manner as in the case of 5×10⁵ TCID₁₀₀/ml. Theaspirated amount of the virus suspension at the concentration of 5×10⁵TCID₁₀₀/ml was 1 ml, while the aspirated amount of the virus suspensionat the concentration of 5×10⁴ TCID₁₀₀/ml was 10 ml, which is ten timesmore than that of the 5×10⁵ TCID₁₀₀/ml virus suspension. Moreover, theelectric field strength was set to 2 V/cm and the application time was 5minutes, FIG. 7 indicates the results.

While the aspirated amount of the virus suspension was 3 ml in theaforementioned experiment, the aspirated amount was reduced to 1 ml inthis experiment. Ther fore, the absolute amount of the virus concntrated in the conductive hollow fiber membrane was reduced to on -thirdof that in the aforementioned experiment. However, in the case of 5×10⁵TCID₁₀₀/ml, as shown in FIG. 7 (Lane 2), the extraction of the virusgenes was recognized, Subsequently, 10 ml of the virus suspension at theconcentration of 5×10⁴ TCID₁₀₀/ml, from which virus genes had not beenextracted, was aspirated to extract the virus genes. As a result, asshown in FIG. 7 (Lane 3), the gene band was confirmed. This indicatesthat, just as in the case of aspiration of 1 ml virus suspension at theconcentration of 5×10⁵ TCID₁₀₀/ml, 5×10⁵ virus genes were concentratedin the conductive hollow fiber membrane.

Concerning a conventional method of virus concentration, it is necessaryto perform the concentration for a long period of time by using anultracentrifuge. On the other hand, it is evident that virusconcentration using the conductive hollow fiber membrane as per thisinvention is a very effective means.

In this embodiment, the concentration speed of the virus suspension wasset to approximately 0.6 ml/min, but the concentration speed depends onthe aspiration speed of the pump. Therefore, it is possible to controlthe concentration speed by means of the pump, and to further shorten thetime.

As described above, only 5 μl out of the 1.5 ml solution in the cathodarea, in which the gene extraction operation was conducted, was used forthe PCR. In other words, only one-three hundredths ( 1/300) of theentire amount of the genes extracted from the conductive hollow fibermembrane exists in this 5 μl. Ther fore, an examination was conducted tosee if the extraction sensitivity could be improved by newly adding thefollowing gene concentration operation after the extraction of th virusgenes.

After the virus concentration and the lysing were conducted in the samemanner as described above, the semipermeable membranes were placed inthe electrophoresis tank to divide the tank into three areas, and theconductive hollow fiber membrane module was set in a central area of thethree areas in the electrophoresis tank, and a platinum wire was set ineither one of the remaining two areas. Then, the conductive hollow fibermembrane module was made to operate as the cathode, and the platinumwire was made to operate as the anode, and the electric field with thestrength of 2 V/cm was applied for 5 minutes, thereby electricallyextracting the genes from the conductive hollow fiber membrane module.However, since the buffer solution for electrophoresis (1.5 ml), towhich 1% glycerin was added, was used in the central area, the physicalextraction operation to force out the solution was not conducted.Subsequently, the conductive hollow fiber membrane module was moved tothe other remaining area and the electric field with the strength of 2V/cm was applied for 10 minutes, thereby causing the genes existing inthe central area to be concentrated on the surface of the semipermeablemembrane on the platinum wire side. Finally, a part of the semipermeablemembrane was cut and placed in a PCR reactant solution, therebyamplifying the target genes. FIG. 8 shows the results. Referring to FIG.8, the gene bands can be recognized in the case of 5×10⁵ TCID₁₀₀/ml andalso in the case of 5×10⁴ TCID₁₀₀/ml from which no virus genes have beenextracted.

As described above, this invention makes it possible to perform virusconcentration by using the conductive hollow fiber membrane.Accordingly, the virus concentration that has conventionally requiredthe ultracentrifugal op ration for a long period of time can beconducted for a short period of time (for example, for about 10 minuteswith regard to the specimen amount of 6 ml). Moreover, this inventioncan provide a method of extracting virus genes, which is excellent inquickness and convenience and can be automated, and this invention canalso provide the apparatus for such extraction of virus genes.

1. A method of extracting virus genes from a virus suspension,comprising the steps of: immersing a conductive hollow fiber membrane inthe virus suspension and thereby capturing, in the conductive hollowfiber membrane, viruses suspended in the virus suspension; lysing thecoating of the captured viruses and releasing the virus genes; andcollecting the virus genes by subjecting, after the lysing step, theconductive hollow fiber membrane to at least one of an electricaltreatment and a physical treatment wherein said electrical treatmentincludes a step of conducting electrophoresis by energizing theconductive hollow fiber membrane so that the conductive hollow fibermembrane becomes a cathode, and wherein said physical treatment includesa step of forcing material that has previously passed through theconductive hollow fiber membrane, against the conductive hollow fibermembrane, in a reverse direction to its previous passage.
 2. The methodof extracting virus genes according to claim 1, wherein the capturingstep includes a step of aspirating the virus suspension via theconductive hollow fiber membrane.
 3. The method of extracting virusgenes according to claim 2, wherein the material comprises the virussuspension that has been aspirated in the aspirating step.
 4. The methodof extracting virus genes according to claim 1, wherein the electricaltreatment and the physical treatment are conducted at the same time. 5.The method of extracting virus genes according to claim 1, wherein thecoating of the viruses is lysed chemically in the lysing step.
 6. Themethod of extracting virus genes according to claim 1, wherein theelectrophoresis step is conducted by placing a semipermeable membranebetween the cathode area and an anode area.
 7. A virus gene extractingapparatus for extracting virus genes from a virus suspension,comprising: a conductive hollow fiber membrane immersed in the virussuspension and capturing viruses in the virus suspension; a lysingliquid for lysing the coating of the viruses captured in the conductivehollow fiber membrane and releasing the virus genes; and agene-collecting device which is capable of receiving the conductivehollow fiber member with the released virus genes captured therein, andwhich applies at least one of an electrical treatment and a physicaltreatment to the virus genes captured in the conductive hollow fibermembrane, thereby collecting the virus genes; the gene-collecting devicecomprising at least one of (i) an energizing device for energizing theconductive hollow fiber membrane so that the conductive hollow fibermembrane becomes a cathode and (ii) a mechanism for forcing materialthat has previously passed through the conductive hollow fiber membrane,against the conductive hollow fiber membrane, in a reverse direction toits previous passage.
 8. The virus gene extracting apparatus accordingto claim 7, further comprising a pump that is connected to theconductive hollow fiber membrane and is capable of aspirating the virussuspension via the conductive hollow fiber membrane.
 9. The virus geneextracting apparatus according to claim 7, wherein the gene-collectingdevice includes a mechanism for forcing against the conductive hollowfiber membrane, the virus suspension that has been aspirated by thepump.
 10. The virus gene extracting apparatus according to claim 9,wherein a semipermeable membrane is placed between the cathode area andthe anode area of the gene-collecting device.